Proper axle alignment in road vehicles is important to prevent undue tire wear. Some common causes of improper wheel alignment in road vehicles include improper initial suspension system installation, accident damage and impact or shock loads imposed on suspension components by potholes and other road irregularities.
Various wheel alignment adjustment systems have been provided to permit adjustment of vehicle axles and wheels to proper alignment. For example, U.S. Pat. No. 2,674,465 issued Apr. 6, 1954, discloses an alignment device for automobile wheels wherein complementary notched plates are adjustable with respect to each other to adjust the camber axis of the vehicle axle.
U.S. Pat. No. 2,065,071 issued Dec. 22, 1936, discloses another device for adjusting the camber axis of a vehicle wheel including an eccentric bushing which is mounted within a cylindrical bushing for rotation with respect thereto. The cylindrical bushing has an outer serrated surface which mates with a serrated lock washer on a bolt that is tightened down to secure the lock washer with respect to the cylindrical bushing and thereby fix the relative rotary positions of the eccentric and cylindrical bushings.
U.S. Pat. No. 2,162,828 issued June 20, 1939, discloses a suspension system for camber adjustment between a steering knuckle support pin and attached links or arms. Serrations on each end of the support pin mate with complementary serrations on the ends of the attached arms to lock the support pin in position with respect thereto. The arms have elongated slots in which securing pins are mounted such that adjustment of the securing pins in the elongated slots will serve to adjust the camber axis of the vehicle axle.
U.S. Pat. No. 3,163,441 issued Dec. 29, 1964, discloses another device for adjusting the camber axis of a vehicle axle in which an eccentric bushing is maintained in position by a serrated washer which bites into adjacent surfaces and further by a lock washer and associated pressure plate which have complementary serrated surfaces.
U.S. Pat. No. 4,202,564 issued May 13, 1980, discloses a bushing which has serrated surfaces that mate with complementary serrated surfaces in mounting blocks to maintain a selected position of the bushing with respect to a surrounding sleeve.
U.S. Pat. No. 3,229,959 issued Jan. 18, 1966, discloses a caster and camber adjustment mechanism for a vehicle axle in which a mounting block has serrated surfaces which engage complementary serrated surfaces on a frame. The camber and caster angles are adjusted by releasing a clamp device and rotating the mounting block with respect to the frame.
U.S. Pat. No. 2,846,250 issued Aug. 5, 1958, discloses the adjustment of struts in a jet engine by an alignment block having an elongated opening and serrated surfaces on both sides thereof to mate with complementary serrated surfaces on a strut and on the frame to which the strut is secured. Once the proper alignment is achieved a permanent locking pin is installed to ensure permanent maintenance of the aligned position.
U.S. Pat. No. Re 30,308 originally issued Dec. 9, 1969, discloses a vehicle suspension including vertically swingable control arms wherein the pivot connections between the control arms and the vehicle frame, or between the control arms and the axle, include a pair of alignment plates carried by the pivot pin closely adjacent to respective opposite sides of the vehicle bracket to which the control arm is pivotally connected. The installed pivot pin assembly is movable laterally with respect to the vehicle frame, but is laterally fixed with respect to the alignment plates. Alignment may be achieved upon initial control arm installation by clamping the pivot pin assembly (i.e. as by tightening down a pivot bolt) in properly aligned orientation and then welding the alignment plates to the frame.